1. Field of the Invention
This invention relates to a packing in or for a vessel to contact fluid therein.
The vessel may be a heat exchange tube for heating or cooling of fluid flowing through the tube and in this case packing improves the efficiency of heat transfer.
Alternatively, the vessel may be a fluid treatment apparatus such as a fluid-fluid or fluid-solid or fluid-fluid-solid contacting, de-entraining and/or coalescing, or extraction or liquid vapor distillation or liquid-gas absorption or other contacting, de-entraining, physical and/or chemical reactor vessel, tube, column, tower or the like. In this case packing is provided to improve, for example, one or more of the following; separation, distribution or dispersion of fluids, mixing, reacting, separation, distribution or dispersion of a fluid, or fluids and a solid, increasing the rate of diffusion or permeation in tubes used for reverse osmosis and permeation de-humidification, coalescence, drying and the like.
The above uses of a vessel having a packing disposed therein are given by way of example and explanation only and are not to be regarded as in any way limiting the scope of the protection to be afforded by this patent since a vessel having a packing disposed therein and embodying the present invention may have other uses.
2. DESCRIPTION OF THE PRIOR ART
GB-PS-483642 discloses a vessel having a single element of packing disposed therein wherein the vessel is a radiator tube for an internal combustion engine and the packing is provided to improve the efficiency of cooling of the fluid in the radiator tube. The packing has very low efficiency due to a low surface area per unit volume and the packing makes poor contact with the walls of the vessel giving high voidage, maldistribution of the fluid, low mass and heat transfer.
GB-PS-1570530 discloses a vessel having a packing disposed therein wherein the vessel comprises a fluid-fluid or fluid-solid contacting, deentrainment or reaction apparatus and the packing comprises a plurality of short articles distributed randomly within the apparatus, each article comprising two elongate members twisted together to form a central core and having trapped therebetween a plurality of convolutions which collectively extend in helical fashion about the central core. This random spring packing, because of the irregularities of the alignment of the packing elements, gives maldistribution of the fluids flowing over the packing. This maldistribution and low efficiency increases as the diameter of the vessel is increased.
GB-2097910 discloses a vessel having a packing comprising a plurality of relatively short inserts, the inserts having a length to diameter ratio not greater than 2:1 and arranged in a relatively large diameter vessel, for example, of 2 meter diameter. The inserts comprising a core having a plurality of loops disposed longitudinally therealong and angularly thereabout and are inclined to the longitudinal axis so that there is no intermeshing of the loops of adjacent side by side inserts with consequent high voidage between adjacent inserts, maldistribution of flow and the usual resultant shortcomings.
U.S. Pat. No. 2,332,110 discloses a vessel having a packing disclosed therein, wherein the vessel comprises a fractionating column. In one embodiment the packing comprises an assembly including a plurality of units, each unit consisting of a wire coiled to form a series of substantially similar loops, the loops forming areas substantially transverse to the path of said flow, the units being symmetrically disposed so that they form a generally circular composite structure with an open region in the center thereof. In a second embodiment the column has a plurality of such packing assemblies disposed therein in side by side relationship and with the part circumferentially extending portions of the looops of adjacent side by side units being separated by wire mesh enclosures which maintain each assembly intact. This packing therefore has low efficiency due to the lower surface area per unit volume of packing and the relatively high voidage giving maldistribution of the fluid.